Reproduction Flashcards
What occurs during G1?
The cell creates organelles and grows in size
What occurs during S?
Genetic material is replicated and is held together by centromere
This does NOT increase the number of chromatids, just gives them the traditional X shape
What occurs during G2?
The cell checks for the correct number of organelles and makes sure DNA is good in order to begin mitosis
Order metaphase, telophase, anaphase and prophase
Prophase
Metaphase
Anaphase
Telophase
A cell spends the longest amount of time in _____ which is made up of 3 phases :_____
Interphase
G1, S, and G2
What occurs during prophase?
-Chromatin condense and become chromosomes
-The nucleoli and nuclear membrane disappear
-Centrioles migrate to either side of the cell and begin to form the mitotic spindle
What occurs during metaphase?
-Spindle fibers connect to the chromosomes by linking with kinetochore fibers
-Chromosomes align at the metaphasic plate (center)
What occurs during anaphase?
-Centromeres split
-Sister chromatids are pulled to either side of the cell
What occurs during telophase?
Reverse of prophase
-Nuclear membrane and nucleoli reform
-Chromosomes relax
-Spindle apparatus disappears
What happens in cytokinesis and when does it occur?
Occurs during telophase
Each daughter cell is given enough organelles and cytoplasm to survive
What is the difference between mitosis and meiosis?
Interphase occurs in both mitosis and meiosis
Mitosis is for growth, occurs in normal body cells and makes identical diploid cells with 46 chromosomes each
Meiosis is for genetic variability, occurs in sex cells (gametes) and makes 4 nonidentical haploid cells with 23 chromosomes each
Meiosis: What occurs in prophase 1?
When the chromosomes line up, they experience cross over and create recombinate genes
Meiosis: What occurs in metaphase 1?
The chromosomes line up in the middle of the cell, but they’re in pairs instead of in one line like in mitosis
Meiosis: What occurs in anaphase 1?
Disjunction occurs –> the homologous chromosomes are pulled to one side of the cell each (split down the middle –> chromosomes on left go to left, chromosomes on right go to right)
Meiosis: What occurs in telophase 1?
Will create two daughter cells with one chromosome each, which can then undergo meiosis 2 to form the uptime 4 haploid cells
-At this point there are 23 chromosomes but 46 chromatids, since they are still duplicated in order to divide during meiosis 2
Order: Luteal phase, menstruation, ovulation, follicular phase
Follicular phase, ovulation, luteal phase, menstruation
How do hormones change during the follicular phase?
GnRH increases as estrogen and progesterone decrease
The increase in GnRH leads to an increase in FSH and LH
At the end of this phase, estrogen starts to increase and shuts off GnRH, LH and FSH
How do hormones change during ovulation?
Estrogen acts in a + feedback that increases the amount of GnRh, LH and FSH
The increase in LH causes an egg to be released
How do hormones change during the luteal phase?
LH causes the secretion of progesterone
Progesterone increase, estrogen remains and the same, and GnRH, LH and FSH decrease
How do hormones change during menstruation?
Since no implantation occurred, progesterone decreases
The decrease of estrogen and progesterone means an increase in GnRH, which begins the phases all over again
Seminiferous tubules
Produce sperm
Interstitial cells of Leydig
Secrete testosterone and other androgens
Cremaster muscle
Raises/lowers testes
Vas deferens
Connects the urethra and epididymis
Seminal vesicles
Contributes fructose for sperm
Prostate gland
Gives sperm alkaline properties to combat the acidic vagina
Cowpers gland
Produces fluid to clear out urine from urethra
The seminal fluid is made by the ___, ____, and ____
Seminal vesicles, prostate and cowper’s gland
Order the following steps of spermatogenesis:
Secondary spermatocyte, spermatogonia, primary spermatocyte, spermatozoa, spermatid
Spermatogonia (diploid), primary spermatocyte (diploid, after S stage), secondary spermatocyte (after meiosis 1), spermatid (after meiosis 2, haploid), spermatozoa (mature sperm)
During ovulation, the oocyte is released from the ____, into the _____, and then pulled into the _____ by cillia
Ovaries, abdominal cavity, fallopian tubes
What role do estrogen and progesterone play in the endometrial lining?
Estrogen thickens the lining while progesterone keeps it in place
What is the process of oogenesis?
-ooctyes are arrested in prophase I until first menstruation
Each month
-Primary oocyte undergoes meiosis I to create polar body (useless) and secondary oocyte
-Secondary oocyte arrests at metaphase II and will resume meiosis II if there’s fertilization
The zona pellicuda is located
Around the ooctye
